Tag Archives: cancer

Reading (2 of 2): Is zinc-infused underwear healthier for women?

This first part of this Reading ‘series’, Reading (1 of 2): an artificial intelligence story in British Columbia (Canada) was mostly about how one type of story, in this case,based on a survey, is presented and placed in one or more media outlets. The desired outcome is for more funding by government and for more investors (they tucked in an ad for an upcoming artificial intelligence conference in British Columbia).

This story about zinc-infused underwear for women also uses science to prove its case and it, too, is about raising money. In this case, it’s a Kickstarter campaign to raise money.

If Huha’s (that’s the company name) claims for ‘zinc-infused mineral undies’ are to be believed, the answer is an unequivocal yes. The reality as per the current research on the topic is not quite as conclusive.

The semiotics (symbolism)

Huha features fruit alongside the pictures of their underwear. You’ll see an orange, papaya, and melon in the kickstarter campaign images and on the company website. It seems to be one of those attempts at subliminal communication. Fruit is good for you therefore our underwear is good for you. In fact, our underwear (just like the fruit) has health benefits.

For a deeper dive into the world of semiotics, there’s the ‘be fruitful and multiply’ stricture which is found in more than one religious or cultural orientation and is hard to dismiss once considered.

There is no reason to add fruit to the images other than to suggest benefits from nature and fertility (or fruitfulness). They’re not selling fruit and these ones are not particularly high in zinc. If all you’re looking for is colour, why not vegetables or puppies?

The claims

I don’t have time to review all of the claims but I’ll highlight a few. My biggest problem with the claims is that there are no citations or links to studies, i.e., the research. So, something like this becomes hard to assess,

Most women’s underwear are made with chemical-based, synthetic fibers that lead to yeast and UTI [urinary tract infection] infections, odor, and discomfort. They’ve also been proven to disrupt human hormones, have been linked to cancer, pollute the planet aggressively, and stay in landfills far too long.

There’s more than one path to a UTI and/or odor and/or discomfort but I can see where fabrics that don’t breathe can exacerbate or cause problems of that nature. I have a little more difficulty with the list that follows. I’d like to see the research on underpants disrupting human hormones. Is this strictly a problem for women or could men also be affected? (If you should know, please leave a comment.)

As for ‘linked to cancer’, I’m coming to the conclusion that everything is linked to cancer. Offhand, I’ve been told peanuts, charcoal broiled items (I think it’s the char), and my negative thoughts are all linked to cancer.

One of the last claims in the excerpted section, ‘pollute the planet aggressively’ raises this question.When did underpants become aggressive’?

The final claim seems unexceptional. Our detritus is staying too long in our landfills. Of course, the next question is: how much faster do the Huha underpants degrade in a landfill? That question is not addressed in Kickstarter campaign material.

Talking to someone with more expertise

I contacted Dr. Andrew Maynard, Associate Director at Arizona State University (ASU) School for the Future of Innovation in Society, He has a PhD in physics and longstanding experience in research and evaluation of emerging technologies (for many years he specialized in nanoparticle analysis and aerosol exposure in occupational settings),.

Professor Maynard is a widely recognized expert and public commentator on emerging technologies and their safe and responsible development and use, and has testified before [US] congressional committees on a number of occasions. 

None of this makes him infallible but I trust that he always works with integrity and bases his opinions on the best information at hand. I’ve always found him to be a reliable source of information.

Here’s what he had to say (from an October 25, 2019 email),

I suspect that their claims are pushing things too far – from what I can tell, professionals tend to advise against synthetic underwear because of the potential build up of moisture and bacteria and the lack of breathability, and tend to suggest natural materials – which indicating that natural fibers and good practices should be all most people need. I haven’t seen any evidence for an underwear crisis here, and one concern is that the company is manufacturing a problem which they then claim to solve. That said, I can’t see anything totally egregious in what they are doing. And the zinc presence makes sense in that it prevents bacterial growth/activity within the fabric, thus reducing the chances of odor and infection.

Pharmaceutical grade zinc and research into underwear

I was a little curious about ‘pharmaceutical grade’ zinc as my online searches for a description were unsuccessful. Andrew explained that the term likely means ‘high purity’ zinc suitable for use in medications rather than the zinc found in roofing panels.

After the reference to ‘pharmaceutical grade’ zinc there’s a reference to ‘smartcel sensitive Zinc’. Here’s more from the smartcel sensitive webpage,

smartcel™ sensitive is skin friendly thanks to zinc oxide’s soothing and anti-inflammatory capabilities. This is especially useful for people with sensitive skin or skin conditions such as eczema or neurodermitis. Since zinc is a component of skin building enzymes, it operates directly on the skin. An active exchange between the fiber and the skin occurs when the garment is worn.

Zinc oxide also acts as a shield against harmful UVA and UVB radiation [it’s used in sunscreens], which can damage our skin cells. Depending on the percentage of smartcel™ sensitive used in any garment, it can provide up to 50 SPF.

Further to this, zinc oxide possesses strong antibacterial properties, especially against odour causing bacteria, which helps to make garments stay fresh longer. *

I couldn’t see how zinc helps the pH balance in anyone’s vagina as claimed in the Kickstarter campaign and smartcel, on its ‘sensitive’ webpage, doesn’t make that claim but I found an answer in an April 4, 2017 Q&A (question and answer) interview by Jocelyn Cavallo for Medium,

What women need to know about their vaginal p

Q & A with Dr. Joanna Ellington

A woman’s vagina is a pretty amazing body part. Not only can it be a source of pleasure but it also can help create and bring new life into the world. On top of all that, it has the extraordinary ability to keep itself clean by secreting natural fluids and maintaining a healthy pH to encourage the growth of good bacteria and discourage harmful bacteria from moving in. Despite being so important, many women are never taught the vital role that pH plays in their vaginal health or how to keep it in balance.

We recently interviewed renowned Reproductive Physiologist and inventor of IsoFresh Balancing Vaginal Gel, Dr. Joanna Ellington, to give us the low down on what every woman needs to know about their vaginal pH and how to maintain a healthy level.

What is pH?

Dr. Ellington: PH is a scale of acidity and alkalinity. The measurements range from 0 to 14: a pH lower than 7 is acidic and a pH higher than 7 is considered alkaline.

What is the “perfect” pH level for a woman’s vagina?

Dr. E.: For most women of a reproductive age vaginal pH should be 4.5 or less. For post-menopausal women this can go up to about 5. The vagina will naturally be at a high pH right after sex, during your period, after you have a baby or during ovulation (your fertile time).

Are there diet and environmental factors that affect a women’s vaginal pH level?

Dr. E.: Yes, iron zinc and manganese have been found to be critical for lactobacillus (healthy bacteria) to function. Many women don’t eat well and should supplement these, especially if they are vegetarian. Additionally, many vegetarians have low estrogen because they do not eat the animal fats that help make our sex steroids. Without estrogen, vaginal pH and bacterial imbalance can occur. It is important that women on these diets ensure good fat intake from other sources, and have estrogen and testosterone and iron levels checked each year.

Do clothing and underwear affect vaginal pH?

Dr. E.: Yes, tight clothing and thong underwear [emphasis mine] have been shown in studies to decrease populations of healthy vaginal bacteria and cause pH changes in the vagina. Even if you wear these sometimes, it is important for your vaginal ecosystem that loose clothing or skirts be worn some too.

Yes, Dr. Ellington has the IsoFresh Balancing Vaginal Gel and whether that’s a good product should be researched but all of the information in the excerpt accords with what I’ve heard over the years and fits in nicely with what Andrew said, zinc in underwear could be useful for its antimicrobial properties. Also, note the reference to ‘thong underwear’ as a possible source of difficulty and note that Huha is offering thong and very high cut underwear.

Of course, your underwear may already have zinc in it as this research suggests (thank you, Andrew, for the reference),

Exposure of women to trace elements through the skin by direct contact with underwear clothing by Thao Nguyen & Mahmoud A. Saleh. Journal of Environmental Science and Health, Part A Toxic/Hazardous Substances and Environmental Engineering Volume 52, 2017 – Issue 1 Pages 1-6 DOI: https://doi.org/10.1080/10934529.2016.1221212 Published online: 09 Sep 2016

This paper is behind a paywall but I have access through a membership in the Canadian Academy of Independent Scholars. So, here’s the part I found interesting,

… The main chemical pollutants present in textiles are dyes containing carcinogenic amines, metals, pentachlorophenol, chlorine bleaching, halogen carriers, free formaldehyde, biocides, fire retardants and softeners.[1] Metals are also found in textile products and clothing are used for many purposes: Co [cobalt], Cu [copper], Cr [chromium] and Pb [lead] are used as metal complex dyes, Cr as pigments mordant, Sn as catalyst in synthetic fabrics and as synergists of flame retardants,Ag [silver] as antimicrobials and Ti [titanium] and Zn [zinc] as water repellents and odor preventive agents.[2–5] When present in textile materials, the toxic elements mentioned above represent not only a major environmental problem in the textile industry but also they may impose potential danger to human health by absorption through the skin.[6,7] [emphasis mine] Chronic exposure to low levels of toxic elements has been associated with a number of adverse human health effects.[8–11] Also exposure to high concentration of elements which are considered as essential for humans such as Cu, Co, Fe [iron], Mn [manganese] or Zn among others, can also be harmful.[12] [emphasis mine] Co, Cr, Cu and Ni [nitrogen] are skin sensitizers,[13,14] which may lead to contact dermatitis, also Cr can lead to liver damage, pulmonary congestion and cancer.[15] [emphasis mine] The purpose of the present study was to determine the concentrations of a number of elements in various skin-contact clothes. For risk estimations, the determination of the extractable amounts of heavy metals is of importance, since they reflect their possible impact on human health. [p. 2 PDF]

So, there’s the link to cancer. Maybe.

Are zinc-infused undies a good idea?

It could go either way. (For specifics about the conclusions reached in the study, scroll down to the Ooops! subheading.) I like the idea of using sustainable Eucalyptus-based material (TencelL) for the underwear as I have heard that cotton isn’t sustainably cultivated. As for claims regarding the product’s environmental friendliness, it’s based on wood, specifically, cellulose, which Canadian researchers have been experimenting with at the nanoscale* and they certainly have been touting nanocellulose as environmentally friendly. Tencel’s sustainability page lists a number of environmental certifications from the European Union, Belgium, and the US.

*Somewhere in the Kickstarter campaign material, there’s a reference to nanofibrils and I’m guessing those nanofibrils are Tencel’s wood fibers at the nanoscale. As well, I’m guessing that smartcel’s fabric contains zinc oxide nanoparticles.

Whether or not you need more zinc is something you need to determine for yourself. Finding out if the pH balance in your vagina is within a healthy range might be a good way to start. It would also be nice to know how much zinc is in the underwear and whether it’s being used antimicrobial properties and/or as a source for one of minerals necessary for your health.

How the Kickstarter campaign is going

At the time of this posting, they’ve reached a little over $24,000 with six days left. The goal was $10,000. Sadly, there are no questions in the FAQ (frequently asked questions).

Reading tips

It’s exhausting trying to track down authenticity. In this case, there were health and environmental claims but I do have a few suggestions.

  1. Look at the imagery critically and try to ignore the hyperbole.
  2. How specific are the claims? e.g., How much zinc is there in the underpants?
  3. Who are their experts and how trustworthy are the agencies/companies mentioned?
  4. If research is cited, are the publishers reputable and is the journal reputable?
  5. Does it make sense given your own experience?
  6. What are the consequences if you make a mistake?

Overblown claims and vague intimations of disease are not usually good signs. Conversely, someone with great credential may not be trustworthy which is why I usually try to find more than one source for confirmation. The person behind this campaign and the Huha company is Alexa Suter. She’s based in Vancouver, Canada and seems to have spent most of her time as a writer and social media and video producer with a few forays into sales and real estate. I wonder if she’s modeling herself and her current lifestyle entrepreneurial effort on Gwyneth Paltrow and her lifestyle company, Goop.

Huha underwear may fulfill its claims or it may be just another pair of underwear or it may be unhealthy. As for the environmentally friendly claims, let’s hope that the case. On a personal level, I’m more hopeful about that.

Regardless, the underwear is not cheap. The smallest pledge that will get your underwear (a three-pack) is $65 CAD.

Ooops! ETA: November 8, 2019:

I forgot to include the conclusion the researchers arrived at and some details on how they arrived at those conclusions. First, they tested 120 pairs of underpants in all sorts of colours and made in different parts of the world.

Second, some underpants showed excessive levels of metals. Cotton was the most likely material to show excess although nylon and polyester can also be problematic. To put this into proportion and with reference to zinc, “Zn exceeded the limit in 4% of the tested samples
and was found mostly in samples manufactured in China.” [p. 6 PDF] Finally, dark colours tested for higher levels of metals than light colours.

While it doesn’t mention underpants as such, there’s a November 8, 2019 article ‘Five things everyone with a vagina should know‘ by Paula McGrath for BBC news online. McGrath’s health expert is Dr. Jen Gunter, a physician whose specialties are obstetrics, gynaecology, and pain.

Skin-based vaccination delivery courtesy of nanotechnology

A May 28, 2019 news item on Nanowerk announced research targeting Langerham cells and the immune system (Note: A link has been removed),

Researchers at the Max Planck Institute of Colloids and Interfaces in Potsdam developed targeted nanoparticles that are taken up by certain immune cells of the human skin (ACS Central Science, “A specific, glycomimetic Langerin ligand for human Langerhans cell targeting”). These so-called Langerhans cells coordinate the immune response and alert the body when pathogens or tumors occur.

This new nanoparticle technology platform enables targeted drug delivery of vaccines or pharmaceuticals to Langerhans cells, triggering a controlled immune response to naturally eradicate the pathogen or tumor.

Internalized nanoparticles (red) in a Langerhans cell (green membrane marker). Specific targeting of these skin immune cells may lead to novel approaches for skin vaccination [weniger] © Langerhans Zellforschung Labor an der Medizinischen Universität Innsbruck Courtesy: Max Planck Institute

A May 28,2019 Max Planck Institute (MPI) press release, which originated the news item, provides further explanations,

The skin is a particularly attractive place for the application of many drugs that affect the immune system, as the appropriate target cells lie directly beneath the skin. These Langerhans cells are able to elicit an immune reaction in the entire body of the patient after local application of an active substance.

Langerhans Cells – Experts of pathogen defense

To develop a targeted drug delivery system, which guides drugs directly to Langerhans cells, one can make use of their natural function: as professional, antigen-presenting cells they detect pathogens, internalize them and present components of these pathogens to effector cells of the immune system (T cells). For detection and uptake, Langerhans cells use receptors on their surface that search the environment for microbes. They especially recognize pathogens by the unique coating of sugar structures on their surface. Langerin, a protein of the C-type lectins family, is such a receptor on Langerhans cells that can detect viruses and bacteria. The specific expression of Langerin on Langerhans cells allows a targeted drug delivery encapsulated in nanoparticleswhile minimizing the side effects.

The research team of Dr. Christoph Rademacher at the Max Planck Institute of Colloids and Interfaces has now been able to exploit the knowledge of the underlying detection mechanisms with atomic resolution: “Based on our insight how immune cells recognize sugars, we developed a synthetic, sugar-like substance that enables nanoparticles to specifically bind to Langerhans cells”, says Dr. Christoph Rademacher. In collaboration with a scientific team from the Laboratory for Langerhans Cell Research of the Medical University of Innsbruck, nanoparticles have been developed that can be incorporated into Langerhans cells of the human skin through this interaction. The researchers thus lay the foundation for further developments, for example to deliver vaccines directly through the skin to the immune cells. “Imagine avoiding needles for vaccination in the future or directly activating the body’s immune system against infections and maybe even cancer”, adds Dr. Christoph Rademacher. Langerhans cells are responsible for activating the immune system systemically. Based on these findings, it may be possible in the future to develop novel vaccines against infections or immunotherapies for the treatment of cancer or autoimmune diseases.

The starting points for this work were the pioneering contributions from Ralph M. Steinman (Nobel Prize 2011) and other scientists who showed the potential of dendritic cells. Langerhans cells are one subset of these cells and are able to trigger an immune response. These findings were subsequently refined for use in cancer therapy. It has been shown that an immune response can be achieved via artificially introduced antigens. Later work confirmed these findings and also demonstrated that human Langerhans cells are also able to activate the immune system, which is particularly interesting for skin vaccination. Targeted delivery of immunomodulators to Langerhans cells would thus be desirable. However, this is often hindered or even prevented by the complex environment of the skin, especially by competing phagocytes in this tissue, such as macrophages. Consequently, pharmaceuticals not taken up by the Langerhans cells, but internalized into bystander cells may lead to unwanted side effects.

Recognition through synthetic sugars

Based on insights on the interaction between Langerin and its natural sugar ligands Christoph Rademacher and his team developed a synthetic ligand, which binds specifically to the receptor on Langerhans cells. For this purpose, synthetic sugars were produced in the laboratory and their interactions with the receptor were examined by nuclear magnetic resonance spectroscopy. With this method the researchers were able to determine which atoms of the ligand interact with which parts of the receptor. By using this structure-based approach they found out that a compound can be anchored and tested on these nanoparticles. These particles are liposomes, which have been used for many years in the clinic in the absence of such targeting ligands as a carrier for various drugs. The difference with existing systems is that the sugar-like ligand now allows specific binding to Langerhans cells. The investigations on these immune cells were carried out in collaboration with the research group of Assoz. Prof. Patrizia Stoitzner at the Langerhans Cell Research Laboratory of the Medical University of Innsbruck. Together they could show that the specific uptake of liposomes is possible even in the complex environment of human skin. The scientists used different methods such as flow cytometry and confocal microscopy for their findings.

These liposomal particles may now provide a common platform for researchers at the MPI of Colloids and Interfaces to work on the development of novel vaccines in the future.

Here’s a link to and a citation for the paper,

A Specific, Glycomimetic Langerin Ligand for Human Langerhans Cell Targeting by Eike-Christian Wamhoff, Jessica Schulze, Lydia Bellmann, Mareike Rentzsch, Gunnar Bachem, Felix F. Fuchsberger, Juliane Rademacher, Martin Hermann, Barbara Del Frari, Rob van Dalen, David Hartmann, Nina M. van Sorge, Oliver Seitz, Patrizia Stoitzner, Christoph Rademacher. ACS Cent. Sci.201955808-820 DOI: https://doi.org/10.1021/acscentsci.9b00093 Publication Date: May 10, 2019 Copyright © 2019 American Chemical Society

This paper appears to be open access.

Art/science and a paintable diagnostic test for cancer

One of Joseph Cohen’s painting incorporating carbon nanotubes photographed in normal light. Photo courtesy of Joseph Cohen. [downloaded from https://news.artnet.com/art-world/carbon-nanotube-cancer-paint-1638340?utm_content=from_&utm_source=Sailthru&utm_medium=email&utm_campaign=Global%20September%202%20PM&utm_term=artnet%20News%20Daily%20Newsletter%20USE%20%2830%20Day%20Engaged%20Only%29]

The artist credited with the work seen in the above, Joseph Cohen, has done something remarkable with carbon nanotubes (CNTs). Something even more remarkable than the painting as Sarah Cascone recounts in her August 30, 2019 article for artnet.com (Note: A link has been removed),

Not every artist can say that his or her work is helping in the fight against cancer. But over the past several years, Joseph Cohen has done just that, working to develop a new, high-tech paint that can be used not only on canvas, but also to detect cancers and medical conditions such as hypertension and diabetes.

Sloan Kettering Institute scientist Daniel Heller first suggested that Cohen come work at his lab after seeing the artist’s work, which is often made with pigments that incorporate diamond dust and gold, at the DeBuck Gallery in New York.

“We initially thought that in working with an artist, we would make art to shed a little light on our science for the public,” Heller told the Memorial Sloan Kettering blog. “But the collaboration actually taught us something that could help us shine a light on cancer.”

For Cohen, the project was initially intended to develop a new way of art-making. In Heller’s lab, he worked with carbon nanotubes, which Heller was already employing in cancer research, for their optical properties. “They fluoresce in the infrared spectrum,” Cohen says. “That gives artists the opportunity to create paintings in a new spectrum, with a whole new palette of colors.”

Because human eyesight is limited, we can’t actually see infrared fluorescence. But using a special short-wave infrared camera, Cohen is able to document otherwise invisible effects, revealing the carbon nanotube paint’s hidden colors.

“What you’re perceiving as a static painting is actually in motion,” Cohen says. “I’m creating paintings that exist outside of the visible experience.”

Art Supplies—and a Diagnostic Tool

That same imaging technique can be used by doctors looking for microalbuminuria, a condition that causes the kidneys to leak trace amounts of albumin into urine, which is an early sign of of several cancers, diabetes, and high blood pressure.

Cohen helped co-author a paper published this month in Nature Communications about using the nanosensor paint in litmus paper tests with patient urine samples. The study found that the paint, when viewed through infrared light, was able to reveal the presence of albumin based on changes in the paint’s fluorescence after being exposed to the urine sample.

“It’s easy to detect albumen with a dipstick if there’s a lot of levels in the urine, but that would be like looking at stage four cancer,” Cohen says. “This is early detection.”

What’s more, a nanosensor paint can be easily used around the world, even in poor areas that don’t have access to the best diagnostic technologies. Doctors may even be able to view the urine samples using an infrared imaging attachments on their smartphones.

One of Joseph Cohen’s painting incorporating carbon nanotubes shown in both the visible light (left) and in UV fluorescence (right). Photo courtesy of Joseph Cohen. [downloaded from https://news.artnet.com/art-world/carbon-nanotube-cancer-paint-1638340?utm_content=from_&utm_source=Sailthru&utm_medium=email&utm_campaign=Global%20September%202%20PM&utm_term=artnet%20News%20Daily%20Newsletter%20USE%20%2830%20Day%20Engaged%20Only%29]

Amazing, eh? If you have the time, do read Cascone’s article in its entirety and should your curiosity be insatiable, there’s also an August 22, 2019 posting by Jim Stallard on the Memorial Sloan Kettering Cancer Center blog,

Here’s a link to and a citation for the paper,

Synthetic molecular recognition nanosensor paint for microalbuminuria by Januka Budhathoki-Uprety, Janki Shah, Joshua A. Korsen, Alysandria E. Wayne, Thomas V. Galassi, Joseph R. Cohen, Jackson D. Harvey, Prakrit V. Jena, Lakshmi V. Ramanathan, Edgar A. Jaimes & Daniel A. Heller. Nature Communicationsvolume 10, Article number: 3605 (2019) DOI: https://doi.org/10.1038/s41467-019-11583-1 Published: 09 August 2019

This paper is open access.

Joseph Cohen has graced this blog before in a May 3, 2019 posting titled, Where do I stand? a graphene artwork. It seems Cohen is very invested in using nanoscale carbon particles for his art.

Breakthrough with Alpaca nanobodies

Caption: Bryson and Sanchez, two alpacas who produce unusually small antibodies. These ‘nanobodies’ could help highly promising CAR T-cell therapies kill solid tumors, where right now they work only in blood cancers. Credit: Courtesy of Boston Children’s Hospital

Bryson and Sanchez are not the first camelids to grace this blog. ‘Llam’ me lend you some antibodies—antibody particles extracted from camels and llamas, a June 12, 2014 posting, and Llama-derived nanobodies are good for solving crystal structure, a December 14, 2017 posting, both feature news about medical breakthroughs with regard to the antibodies found in Llamas, camels, and other camelids (including alpacas) could enable.

The latest camelid-oriented medical research story is in an April 11, 2019 news item on phys.org (Note: A link has been removed),

In 1989, two undergraduate students at the Free University of Brussels were asked to test frozen blood serum from camels, and stumbled on a previously unknown kind of antibody. It was a miniaturized version of a human antibody, made up only of two heavy protein chains, rather than two light and two heavy chains. As they eventually reported, the antibodies’ presence was confirmed not only in camels, but also in llamas and alpacas.

Fast forward 30 years. In the journal PNAS [Proceedings of the National Academy of Science] this week [April 8 – 12, 2019], researchers at Boston Children’s Hospital and MIT [Massachusetts Institute of Technology] show that these mini-antibodies, shrunk further to create so-called nanobodies, may help solve a problem in the cancer field: making CAR T-cell therapies work in solid tumors.

An April 11, 2019 Boston Children’s Hospital news release on EurekAlert, which originated the news item, explores the technology,

Highly promising for blood cancers, chimeric antigen receptor (CAR) T-cell therapy genetically engineers a patient’s own T cells to make them better at attacking cancer cells. The Dana-Farber/Boston Children’s Cancer and Blood Disorders Center is currently using CAR T-cell therapy for relapsed acute lymphocytic leukemia (ALL), for example.

But CAR T cells haven’t been good at eliminating solid tumors. It’s been hard to find cancer-specific proteins on solid tumors that could serve as safe targets. Solid tumors are also protected by an extracellular matrix, a supportive web of proteins that acts as a barrier, as well as immunosuppressive molecules that weaken the T-cell attack.

Rethinking CAR T cells

That’s where nanobodies come in. For two decades, they largely remained in the hands of the Belgian team. But that changed after the patent expired in 2013. [emphases mine]

“A lot of people got into the game and began to appreciate nanobodies’ unique properties,” says Hidde Ploegh, PhD, an immunologist in the Program in Cellular and Molecular Medicine at Boston Children’s and senior investigator on the PNAS study.

One useful attribute is their enhanced targeting abilities. Ploegh and his team at Boston Children’s, in collaboration with Noo Jalikhani, PhD, and Richard Hynes, PhD at MIT’s Koch Institute for Integrative Cancer Research, have harnessed nanobodies to carry imaging agents, allowing precise visualization of metastatic cancers.

The Hynes team targeted the nanobodies to the tumors’ extracellular matrix, or ECM — aiming imaging agents not at the cancer cells themselves, but at the environment that surrounds them. Such markers are common to many tumors, but don’t typically appear on normal cells.

“Our lab and the Hynes lab are among the few actively pursuing this approach of targeting the tumor micro-environment,” says Ploegh. “Most labs are looking for tumor-specific antigens.”

Targeting tumor protectors

Ploegh’s lab took this idea to CAR T-cell therapy. His team, including members of the Hynes lab, took aim at the very factors that make solid tumors difficult to treat.

The CAR T cells they created were studded with nanobodies that recognize specific proteins in the tumor environment, bearing signals directing them to kill any cell they bound to. One protein, EIIIB, a variant of fibronectin, is found only on newly formed blood vessels that supply tumors with nutrients. Another, PD-L1, is an immunosuppressive protein that most cancers use to silence approaching T cells.

Biochemist Jessica Ingram, PhD of the Dana-Farber Cancer Institute, Ploegh’s partner and a coauthor on the paper, led the manufacturing pipeline. She would drive to Amherst, Mass., to gather T cells from two alpacas, Bryson and Sanchez, inject them with the antigen of interest and harvest their blood for further processing back in Boston to generate mini-antibodies.

Taking down melanoma and colon cancer

Tested in two separate melanoma mouse models, as well as a colon adenocarcinoma model in mice, the nanobody-based CAR T cells killed tumor cells, significantly slowed tumor growth and improved the animals’ survival, with no readily apparent side effects.

Ploegh thinks that the engineered T cells work through a combination of factors. They caused damage to tumor tissue, which tends to stimulate inflammatory immune responses. Targeting EIIIB may damage blood vessels in a way that decreases blood supply to tumors, while making them more permeable to cancer drugs.

“If you destroy the local blood supply and cause vascular leakage, you could perhaps improve the delivery of other things that might have a harder time getting in,” says Ploegh. “I think we should look at this as part of a combination therapy.”

Future directions

Ploegh thinks his team’s approach could be useful in many solid tumors. He’s particularly interested in testing nanobody-based CAR T cells in models of pancreatic cancer and cholangiocarcinoma, a bile duct cancer from which Ingram passed away in 2018.

The technology itself can be pushed even further, says Ploegh.

“Nanobodies could potentially carry a cytokine to boost the immune response to the tumor, toxic molecules that kill tumor and radioisotopes to irradiate the tumor at close range,” he says. “CAR T cells are the battering ram that would come in to open the door; the other elements would finish the job. In theory, you could equip a single T cell with multiple chimeric antigen receptors and achieve even more precision. That’s something we would like to pursue.”

So, the Belgian researchers have a patent for two decades and, after it expires, more researchers could help to take the work further. Hmm …

Moving on, here’s a link to and a citation for the paper,

Nanobody-based CAR T cells that target the tumor microenvironment inhibit the growth of solid tumors in immunocompetent mice by Yushu Joy Xie, Michael Dougan, Noor Jailkhani, Jessica Ingram, Tao Fang, Laura Kummer, Noor Momin, Novalia Pishesha, Steffen Rickelt, Richard O. Hynes, and Hidde Ploegh. PNAS DOI: https://doi.org/10.1073/pnas.1817147116
First published April 1, 2019

This paper is behind a paywall

The CRISPR ((clustered regularly interspaced short palindromic repeats)-CAS9 gene-editing technique may cause new genetic damage kerfuffle

Setting the stage

Not unexpectedly, CRISPR-Cas9  or clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 can be dangerous as these scientists note in a July 16, 2018 news item on phys.org,

Scientists at the Wellcome Sanger Institute have discovered that CRISPR/Cas9 gene editing can cause greater genetic damage in cells than was previously thought. These results create safety implications for gene therapies using CRISPR/Cas9 in the future as the unexpected damage could lead to dangerous changes in some cells.

Reported today (16 July 2018) in the journal Nature Biotechnology, the study also revealed that standard tests for detecting DNA changes miss finding this genetic damage, and that caution and specific testing will be required for any potential gene therapies.

This CRISPR-Cas9 image reminds me of popcorn,

CRISPR-associated protein Cas9 (white) from Staphylococcus aureus based on Protein Database ID 5AXW. Credit: Thomas Splettstoesser (Wikipedia, CC BY-SA 4.0)[ downloaded from https://phys.org/news/2018-07-genome-crisprcas9-gene-higher-thought.html#jCp]

A July 16, 2018 Wellcome Sanger Institute press release (also on EurekAlert), which originated the news item, offers a little more explanation,

CRISPR/Cas9 is one of the newest genome editing tools. It can alter sections of DNA in cells by cutting at specific points and introducing changes at that location. Already extensively used in scientific research, CRISPR/Cas9 has also been seen as a promising way to create potential genome editing treatments for diseases such as HIV, cancer or sickle cell disease. Such therapeutics could inactivate a disease-causing gene, or correct a genetic mutation. However, any potential treatments would have to prove that they were safe.

Previous research had not shown many unforeseen mutations from CRISPR/Cas9 in the DNA at the genome editing target site. To investigate this further the researchers carried out a full systematic study in both mouse and human cells and discovered that CRISPR/Cas9 frequently caused extensive mutations, but at a greater distance from the target site.

The researchers found many of the cells had large genetic rearrangements such as DNA deletions and insertions. These could lead to important genes being switched on or off, which could have major implications for CRISPR/Cas9 use in therapies. In addition, some of these changes were too far away from the target site to be seen with standard genotyping methods.

Prof Allan Bradley, corresponding author on the study from the Wellcome Sanger Institute, said: “This is the first systematic assessment of unexpected events resulting from CRISPR/Cas9 editing in therapeutically relevant cells, and we found that changes in the DNA have been seriously underestimated before now. It is important that anyone thinking of using this technology for gene therapy proceeds with caution, and looks very carefully to check for possible harmful effects.”

Michael Kosicki, the first author from the Wellcome Sanger Institute, said: “My initial experiment used CRISPR/Cas9 as a tool to study gene activity, however it became clear that something unexpected was happening. Once we realised the extent of the genetic rearrangements we studied it systematically, looking at different genes and different therapeutically relevant cell lines, and showed that the CRISPR/Cas9 effects held true.”

The work has implications for how CRISPR/Cas9 is used therapeutically and is likely to re-spark researchers’ interest in finding alternatives to the standard CRISPR/Cas9 method for gene editing.

Prof Maria Jasin, an independent researcher from Memorial Slone Kettering Cancer Centre, New York, who was not involved in the study said: “This study is the first to assess the repertoire of genomic damage arising at a CRISPR/Cas9 cleavage site. While it is not known if genomic sites in other cell lines will be affected in the same way, this study shows that further research and specific testing is needed before CRISPR/Cas9 is used clinically.”

For anyone who’d like to better understand the terms gene editing and CRISPR-Cas9, the Wellcome Sanger Institute provides these explanatory webpages, What is genome editing? and What is CRISPR-Cas9?

For the more advanced, here’s a link and a citation for the paper,

Repair of double-strand breaks induced by CRISPR–Cas9 leads to large deletions and complex rearrangements by Michael Kosicki, Kärt Tomberg, & Allan Bradley. Nature Biotechnology DOI: https://doi.org/10.1038/nbt.4192 Published 16 July 2018

This paper appears to be open access.

The kerfuffle

It seems this news has affected the CRISPR market. From a July 16, 2018 article by Cale Guthrie Weissman for Fast Company,

… CRISPR could unknowingly delete or alter non-targeted genes, which could lead to myriad unintended consequences. This is especially frightening, since the technology is going to be used in human clinical trials.

Meanwhile, other scientists working with CRISPR are trying to downplay the findings, telling STAT [a life sciences and business journalism website] that there have been no reported adverse effects similar to what the study describes. The news, however, has brought about a market reaction–at least three publicly traded companies that focus on CRISPR-based therapies are in stock nosedive. Crispr Therapeutics is down by over 6%; Editas fell by over 3%; and Intellia Therapeutics dropped by over 5%. [emphasis mine]

Damage control

Gaetan Burgio (geneticist, Australian National University)  in a July 16, 2018 essay on phys.org (originating from The Conversation) suggests some calm (Note: Links have been removed),

But a new study has called into question the precision of the technique [CRISPR gene editing technology].

The hope for gene editing is that it will be able to cure and correct diseases. To date, many successes have been reported, including curing deafness in mice, and in altering cells to cure cancer.

Some 17 clinical trials in human patients are registered [emphasis mine] testing gene editing on leukaemias, brain cancers and sickle cell anaemia (where red blood cells are misshaped, causing them to die). Before implementing CRISPR technology in clinics to treat cancer or congenital disorders, we must address whether the technique is safe and accurate.

There are a few options for getting around this problem. One option is to isolate the cells we wish to edit from the body and reinject only the ones we know have been correctly edited.

For example, lymphocytes (white blood cells) that are crucial to killing cancer cells could be taken out of the body, then modified using CRISPR to heighten their cancer-killing properties. The DNA of these cells could be sequenced in detail, and only the cells accurately and specifically gene-modified would be selected and delivered back into the body to kill the cancer cells.

While this strategy is valid for cells we can isolate from the body, some cells, such as neurons and muscles, cannot be removed from the body. These types of cells might not be suitable for gene editing using Cas9 scissors.

Fortunately, researchers have discovered other forms of CRISPR systems that don’t require the DNA to be cut. Some CRISPR systems only cut the RNA, not the DNA (DNA contains genetic instructions, RNA convey the instructions on how to synthesise proteins).

As RNA [ribonucleic acid] remains in our cells only for a specific period of time before being degraded, this would allow us to control the timing and duration of the CRISPR system delivery and reverse it (so the scissors are only functional for a short period of time).

This was found to be successful for dementia in mice. Similarly, some CRISPR systems simply change the letters of the DNA, rather than cutting them. This was successful for specific mutations causing diseases such as hereditary deafness in mice.

I agree with Burgio’s conclusion (not included here) that we have a lot more to learn and I can’t help wondering why there are 17 registered human clinical trials at this point.

Wearable technology: two types of sensors one from the University of Glasgow (Scotland) and the other from the University of British Columbia (Canada)

Sometimes it’s good to try and pull things together.

University of Glasgow and monitoring chronic conditions

A February 23, 2018 news item on phys.org describes the latest wearable tech from the University of Glasgow,

A new type of flexible, wearable sensor could help people with chronic conditions like diabetes avoid the discomfort of regular pin-prick blood tests by monitoring the chemical composition of their sweat instead.

In a new paper published in the journal Biosensors and Bioelectronics, a team of scientists from the University of Glasgow’s School of Engineering outline how they have built a stretchable, wireless system which is capable of measuring the pH level of users’ sweat.

A February 22, 2018 University of Glasgow press release, which originated the news item, expands on the theme,

Ravinder Dahiya

 Courtesy: University of Glasgow

 

Sweat, like blood, contains chemicals generated in the human body, including glucose and urea. Monitoring the levels of those chemicals in sweat could help clinicians diagnose and monitor chronic conditions such as diabetes, kidney disease and some types of cancers without invasive tests which require blood to be drawn from patients.

However, non-invasive, wearable systems require consistent contact with skin to offer the highest-quality monitoring. Current systems are made from rigid materials, making it more difficult to ensure consistent contact, and other potential solutions such as adhesives can irritate skin. Wireless systems which use Bluetooth to transmit their information are also often bulky and power-hungry, requiring frequent recharging.

The University of Glasgow team’s new system is built around an inexpensively-produced sensor capable of measuring pH levels which can stretch and flex to better fit the contours of users’ bodies. Made from a graphite-polyurethane composite and measuring around a single square centimetre, it can stretch up to 53% in length without compromising performance. It will also continue to work after being subjected to flexes of 30% up to 500 times, which the researchers say will allow it to be used comfortably on human skin with minimal impact on the performance of the sensor.

The sensor can transmit its data wirelessly, and without external power, to an accompanying smartphone app called ‘SenseAble’, also developed by the team. The transmissions use near-field communication, a data transmission system found in many current smartphones which is used most often for smartphone payments like ApplePay, via a stretchable RFID antenna integrated into the system – another breakthrough innovation from the research team.

The smartphone app allows users to track pH levels in real time and was demonstrated in the lab using a chemical solution created by the researchers which mimics the composition of human sweat.

The research was led by Professor Ravinder Dahiya, head of the University of Glasgow’s School of Engineering’s Bendable Electronics and Sensing Technologies (BEST) group.

Professor Dahiya said: “Human sweat contains much of the same physiological information that blood does, and its use in diagnostic systems has the significant advantage of not needing to break the skin in order to administer tests.

“Now that we’ve demonstrated that our stretchable system can be used to monitor pH levels, we’ve already begun additional research to expand the capabilities of the sensor and make it a more complete diagnostic system. We’re planning to add sensors capable of measuring glucose, ammonia and urea, for example, and ultimately we’d like to see a system ready for market in the next few years.”

The team’s paper, titled ‘Stretchable Wireless System for Sweat pH Monitoring’, is published in Biosensors and Bioelectronics. The research was supported by funding from the European Commission and the Engineering and Physical Sciences Research Council (EPSRC).

Here’s a link to and a citation for the paper,

Stretchable wireless system for sweat pH monitoring by Wenting Dang, Libu Manjakkal, William Taube Navaraj, Leandro Lorenzelli, Vincenzo Vinciguerra. Biosensors and Bioelectronics Volume 107, 1 June 2018, Pages 192–202 [Available online February 2018] https://doi.org/10.1016/j.bios.2018.02.025

This paper is behind a paywall.

University of British Columbia (UBC; Okanagan) and monitor bio-signals

This is a completely other type of wearable tech monitor, from a February 22, 2018 UBC news release (also on EurekAlert) by Patty Wellborn (A link has been removed),

Creating the perfect wearable device to monitor muscle movement, heart rate and other tiny bio-signals without breaking the bank has inspired scientists to look for a simpler and more affordable tool.

Now, a team of researchers at UBC’s Okanagan campus have developed a practical way to monitor and interpret human motion, in what may be the missing piece of the puzzle when it comes to wearable technology.

What started as research to create an ultra-stretchable sensor transformed into a sophisticated inter-disciplinary project resulting in a smart wearable device that is capable of sensing and understanding complex human motion, explains School of Engineering Professor Homayoun Najjaran.

The sensor is made by infusing graphene nano-flakes (GNF) into a rubber-like adhesive pad. Najjaran says they then tested the durability of the tiny sensor by stretching it to see if it can maintain accuracy under strains of up to 350 per cent of its original state. The device went through more than 10,000 cycles of stretching and relaxing while maintaining its electrical stability.

“We tested this sensor vigorously,” says Najjaran. “Not only did it maintain its form but more importantly it retained its sensory functionality. We have further demonstrated the efficacy of GNF-Pad as a haptic technology in real-time applications by precisely replicating the human finger gestures using a three-joint robotic finger.”

The goal was to make something that could stretch, be flexible and a reasonable size, and have the required sensitivity, performance, production cost, and robustness. Unlike an inertial measurement unit—an electronic unit that measures force and movement and is used in most step-based wearable technologies—Najjaran says the sensors need to be sensitive enough to respond to different and complex body motions. That includes infinitesimal movements like a heartbeat or a twitch of a finger, to large muscle movements from walking and running.

School of Engineering Professor and study co-author Mina Hoorfar says their results may help manufacturers create the next level of health monitoring and biomedical devices.

“We have introduced an easy and highly repeatable fabrication method to create a highly sensitive sensor with outstanding mechanical and electrical properties at a very low cost,” says Hoorfar.

To demonstrate its practicality, researchers built three wearable devices including a knee band, a wristband and a glove. The wristband monitored heartbeats by sensing the pulse of the artery. In an entirely different range of motion, the finger and knee bands monitored finger gestures and larger scale muscle movements during walking, running, sitting down and standing up. The results, says Hoorfar, indicate an inexpensive device that has a high-level of sensitivity, selectivity and durability.

Hoorfar and Najjaran are both members of the Okanagan node of UBC’s STITCH (SmarT Innovations for Technology Connected Health) Institute that creates and investigates advanced wearable devices.

The research, partially funded by the Natural Sciences and Engineering Research Council, was recently published in the Journal of Sensors and Actuators A: Physical.

Here’s a link to and a citation for the paper,

Low-cost ultra-stretchable strain sensors for monitoring human motion and bio-signals by Seyed Reza Larimi, Hojatollah Rezaei Nejad, Michael Oyatsi, Allen O’Brien, Mina Hoorfar, Homayoun Najjaran. Sensors and Actuators A: Physical Volume 271, 1 March 2018, Pages 182-191 [Published online February 2018] https://doi.org/10.1016/j.sna.2018.01.028

This paper is behind a paywall.

Final comments

The term ‘wearable tech’ covers a lot of ground. In addition to sensors, there are materials that harvest energy, detect poisons, etc.  making for a diverse field.

CRISPR-Cas12a as a new diagnostic tool

Similar to Cas9, Cas12a is has an added feature as noted in this February 15, 2018 news item on ScienceDaily,

Utilizing an unsuspected activity of the CRISPR-Cas12a protein, researchers created a simple diagnostic system called DETECTR to analyze cells, blood, saliva, urine and stool to detect genetic mutations, cancer and antibiotic resistance and also diagnose bacterial and viral infections. The scientists discovered that when Cas12a binds its double-stranded DNA target, it indiscriminately chews up all single-stranded DNA. They then created reporter molecules attached to single-stranded DNA to signal when Cas12a finds its target.

A February 15, 2018 University of California at Berkeley (UC Berkeley) news release by Robert Sanders and which originated the news item, provides more detail and history,

CRISPR-Cas12a, one of the DNA-cutting proteins revolutionizing biology today, has an unexpected side effect that makes it an ideal enzyme for simple, rapid and accurate disease diagnostics.

blood in test tube

(iStock)

Cas12a, discovered in 2015 and originally called Cpf1, is like the well-known Cas9 protein that UC Berkeley’s Jennifer Doudna and colleague Emmanuelle Charpentier turned into a powerful gene-editing tool in 2012.

CRISPR-Cas9 has supercharged biological research in a mere six years, speeding up exploration of the causes of disease and sparking many potential new therapies. Cas12a was a major addition to the gene-cutting toolbox, able to cut double-stranded DNA at places that Cas9 can’t, and, because it leaves ragged edges, perhaps easier to use when inserting a new gene at the DNA cut.

But co-first authors Janice Chen, Enbo Ma and Lucas Harrington in Doudna’s lab discovered that when Cas12a binds and cuts a targeted double-stranded DNA sequence, it unexpectedly unleashes indiscriminate cutting of all single-stranded DNA in a test tube.

Most of the DNA in a cell is in the form of a double-stranded helix, so this is not necessarily a problem for gene-editing applications. But it does allow researchers to use a single-stranded “reporter” molecule with the CRISPR-Cas12a protein, which produces an unambiguous fluorescent signal when Cas12a has found its target.

“We continue to be fascinated by the functions of bacterial CRISPR systems and how mechanistic understanding leads to opportunities for new technologies,” said Doudna, a professor of molecular and cell biology and of chemistry and a Howard Hughes Medical Institute investigator.

DETECTR diagnostics

The new DETECTR system based on CRISPR-Cas12a can analyze cells, blood, saliva, urine and stool to detect genetic mutations, cancer and antibiotic resistance as well as diagnose bacterial and viral infections. Target DNA is amplified by RPA to make it easier for Cas12a to find it and bind, unleashing indiscriminate cutting of single-stranded DNA, including DNA attached to a fluorescent marker (gold star) that tells researchers that Cas12a has found its target.

The UC Berkeley researchers, along with their colleagues at UC San Francisco, will publish their findings Feb. 15 [2018] via the journal Science’s fast-track service, First Release.

The researchers developed a diagnostic system they dubbed the DNA Endonuclease Targeted CRISPR Trans Reporter, or DETECTR, for quick and easy point-of-care detection of even small amounts of DNA in clinical samples. It involves adding all reagents in a single reaction: CRISPR-Cas12a and its RNA targeting sequence (guide RNA), fluorescent reporter molecule and an isothermal amplification system called recombinase polymerase amplification (RPA), which is similar to polymerase chain reaction (PCR). When warmed to body temperature, RPA rapidly multiplies the number of copies of the target DNA, boosting the chances Cas12a will find one of them, bind and unleash single-strand DNA cutting, resulting in a fluorescent readout.

The UC Berkeley researchers tested this strategy using patient samples containing human papilloma virus (HPV), in collaboration with Joel Palefsky’s lab at UC San Francisco. Using DETECTR, they were able to demonstrate accurate detection of the “high-risk” HPV types 16 and 18 in samples infected with many different HPV types.

“This protein works as a robust tool to detect DNA from a variety of sources,” Chen said. “We want to push the limits of the technology, which is potentially applicable in any point-of-care diagnostic situation where there is a DNA component, including cancer and infectious disease.”

The indiscriminate cutting of all single-stranded DNA, which the researchers discovered holds true for all related Cas12 molecules, but not Cas9, may have unwanted effects in genome editing applications, but more research is needed on this topic, Chen said. During the transcription of genes, for example, the cell briefly creates single strands of DNA that could accidentally be cut by Cas12a.

The activity of the Cas12 proteins is similar to that of another family of CRISPR enzymes, Cas13a, which chew up RNA after binding to a target RNA sequence. Various teams, including Doudna’s, are developing diagnostic tests using Cas13a that could, for example, detect the RNA genome of HIV.

infographic about DETECTR system

(Infographic by the Howard Hughes Medical Institute)

These new tools have been repurposed from their original role in microbes where they serve as adaptive immune systems to fend off viral infections. In these bacteria, Cas proteins store records of past infections and use these “memories” to identify harmful DNA during infections. Cas12a, the protein used in this study, then cuts the invading DNA, saving the bacteria from being taken over by the virus.

The chance discovery of Cas12a’s unusual behavior highlights the importance of basic research, Chen said, since it came from a basic curiosity about the mechanism Cas12a uses to cleave double-stranded DNA.

“It’s cool that, by going after the question of the cleavage mechanism of this protein, we uncovered what we think is a very powerful technology useful in an array of applications,” Chen said.

Here’s a link to and a citation for the paper,

CRISPR-Cas12a target binding unleashes indiscriminate single-stranded DNase activity by Janice S. Chen, Enbo Ma, Lucas B. Harrington, Maria Da Costa, Xinran Tian, Joel M. Palefsky, Jennifer A. Doudna. Science 15 Feb 2018: eaar6245 DOI: 10.1126/science.aar6245

This paper is behind a paywall.

Colliding organic nanoparticles caught on camera for the first time

There is high excitement about this development in a November 17, 2017 news item on Nanowerk,

A Northwestern University research team is the first to capture on video organic nanoparticles colliding and fusing together. This unprecedented view of “chemistry in motion” will aid Northwestern nanoscientists developing new drug delivery methods as well as demonstrate to researchers around the globe how an emerging imaging technique opens a new window on a very tiny world.

A November 17, 2017 Northwestern University news release (also on EurekAlert) by Megan Fellman, which originated the news item, further illuminates the matter,

This is a rare example of particles in motion. The dynamics are reminiscent of two bubbles coming together and merging into one: first they join and have a membrane between them, but then they fuse and become one larger bubble.

“I had an image in my mind, but the first time I saw these fusing nanoparticles in black and white was amazing,” said professor Nathan C. Gianneschi, who led the interdisciplinary study and works at the intersection of nanotechnology and biomedicine.

“To me, it’s literally a window opening up to this world you have always known was there, but now you’ve finally got an image of it. I liken it to the first time I saw Jupiter’s moons through a telescope. Nothing compares to actually seeing,” he said.

Gianneschi is the Jacob and Rosaline Cohn Professor in the department of chemistry in the Weinberg College of Arts and Sciences and in the departments of materials science and engineering and of biomedical engineering in the McCormick School of Engineering.

The study, which includes videos of different nanoparticle fusion events, was published today (Nov. 1 [2017]7) by the Journal of the American Chemical Society.

The research team used liquid-cell transmission electron microscopy to directly image how polymer-based nanoparticles, or micelles, that Gianneschi’s lab is developing for treating cancer and heart attacks change over time. The powerful new technique enabled the scientists to directly observe the particles’ transformation and characterize their dynamics.

“We can see on the molecular level how the polymeric matter rearranges when the particles fuse into one object,” said Lucas R. Parent, first author of the paper and a National Institutes of Health Postdoctoral Fellow in Gianneschi’s research group. “This is the first study of many to come in which researchers will use this method to look at all kinds of dynamic phenomena in organic materials systems on the nanoscale.”

In the Northwestern study, organic particles in water bounce off each other, and some collide and merge, undergoing a physical transformation. The researchers capture the action by shining an electron beam through the sample. The tiny particles — the largest are only approximately 200 nanometers in diameter — cast shadows that are captured directly by a camera below.

“We’ve observed classical fusion behavior on the nanoscale,” said Gianneschi, a member of Northwestern’s International Institute for Nanotechnology. “Capturing the fundamental growth and evolution processes of these particles in motion will help us immensely in our work with synthetic materials and their interactions with biological systems.”

The National Institutes of Health, the National Science Foundation, the Air Force Office of Scientific Research and the Army Research Office supported the research.

Here’s a link to and a citation for the paper,

Directly Observing Micelle Fusion and Growth in Solution by Liquid-Cell Transmission Electron Microscopy by Lucas R. Parent, Evangelos Bakalis, Abelardo Ramírez-Hernández, Jacquelin K. Kammeyer, Chiwoo Park, Juan de Pablo, Francesco Zerbetto, Joseph P. Patterson, and Nathan C. Gianneschi. J. Am. Chem. Soc., Article ASAP DOI: 10.1021/jacs.7b09060 Publication Date (Web): November 17, 2017

Copyright © 2017 American Chemical Society

This paper is behind a paywall.

Hit and run gene therapy?

The approach looks promising but there’s a still long way to go before this ‘simpler, gentler’ approach to gene therapy will make its way into any treatments. From an August 30, 2017 news item on Nanowerk,

A new biomedical tool using nanoparticles that deliver transient gene changes to targeted cells could make therapies for a variety of diseases — including cancer, diabetes and HIV — faster and cheaper to develop, and more customizable.

The tool, developed by researchers at Fred Hutchinson Cancer Research Center and tested in preclinical models, is described in a paper published August 30 [2017] in Nature Communications.

This animation demonstrates the approach,

Biodegradable nanoparticles (orange) carry short-lived gene therapy to specific cells (light teal). Animation by Kimberly Carney / Fred Hutch News Service

An August 30, 2017 Fred Hutchinson Cancer Research Center (Fred Hutch) news release (from news release received via email; also on EurekAlert) by Sabrina Richards, which originated the news item, elucidates further (Note: Some links and notes have been removed),

“Our goal is to streamline the manufacture of cell-based therapies,” said lead author DR. MATTHIAS STEPHAN [6], a faculty member in the Fred Hutch Clinical Research Division and an expert in developing biomaterials. “In this study, we created a product where you just add it to cultured cells and that’s it — no additional manufacturing steps.”

Stephan and his colleagues developed a nanoparticle delivery system to extend the therapeutic potential of messenger RNA, which delivers molecular instructions from DNA to cells in the body, directing them to make proteins to prevent or fight disease.

The researchers’ approach was designed to zero in on specific cell types — T cells of the immune system and blood stem cells — and deliver mRNA directly to the cells, triggering short-term gene expression. It’s called “hit-and-run” genetic programming because the transient effect of mRNA does not change the DNA, but it is enough to make a permanent impact on the cells’ therapeutic potential.

Stephan and colleagues used three examples in the Nature Communications paper to demonstrate their technology:

* Nanoparticles carried a gene-editing tool to T cells of the immune system that snipped out their natural T-cell receptors, and then was paired with genes encoding a “chimeric antigen receptor” or CAR, a synthetic molecule designed to attack cancer.
* Targeted to blood stem cells, nanoparticles were equipped with mRNA that enabled the stem cells to multiply and replace blood cancer cells with healthy cells when used in bone marrow transplants.
* Nanoparticles targeted to CAR-T cells and containing foxo1 mRNA, which signals the anti-cancer T cells to develop into a type of “memory” cell that is more aggressive and destroys tumor cells more effectively and maintains anti-tumor activity longer.

Other attempts to engineer mRNA into disease-fighting cells have been tricky. The large messenger molecule degrades quickly before it can have an effect, and the body’s immune system recognizes it as foreign — not coming from DNA in the nucleus of the cell — and destroys it.

Stephan and his Fred Hutch collaborators devised a workaround to those hurdles.

“We developed a nanocarrier that binds and condenses synthetic mRNA and protects it from degradation,” Stephan said. The researchers surrounded the nanoparticle with a negatively charged envelope with a targeting ligand attached to the surface so that the particle selectively homes in and binds to a particular cell type.

The cells swallow up the tiny carrier, which can be loaded with different types of manmade mRNA. “If you know from the scientific literature that a signaling pathway works in synergy, you could co-deliver mRNA in a single nanoparticle,” Stephan said. “Every cell that takes up the nanoparticle can express both.”

The approach involves mixing the freeze-dried nanoparticles with water and a sample of cells. Within four hours, cells start showing signs that the editing has taken effect. Boosters can be given if needed. Made from a dissolving biomaterial, the nanoparticles are removed from the body like other cell waste.

“Just add water to our freeze-dried product,” Stephan said. Since it’s built on existing technologies and doesn’t require knowledge of nanotechnology, he intends for it to be an off-the-shelf way for cell-therapy engineers to develop new approaches to treating a variety of diseases.

The approach could replace labor-intensive electroporation, a multistep cell-manufacturing technique that requires specialized equipment and clean rooms. All the handling ends up destroying many of the cells, which limits the amount that can be used in treatments for patients.

Gentler to cells, the nanoparticle system developed by the Fred Hutch team showed that up to 60 times more cells survive the process compared with electroporation. This is a critical feature for ensuring enough cells are viable when transferred to patients.

“You can imagine taking the nanoparticles, injecting them into a patient and then you don’t have to culture cells at all anymore,” he said.

Stephan has tested the technology is cultured cells in the lab, and it’s not yet available as a treatment. Stephan is looking for commercial partners to move the technology toward additional applications and into clinical trials where it could be developed into a therapy.

Here’s a link to and a citation for the paper,

Hit-and-run programming of therapeutic cytoreagents using mRNA nanocarriers by H. F. Moffett, M. E. Coon, S. Radtke, S. B. Stephan, L. McKnight, A. Lambert, B. L. Stoddard, H. P. Kiem, & M. T. Stephan. Nature Communications 8, Article number: 389 (2017) doi:10.1038/s41467-017-00505-8 Published online: 30 August 2017

This paper is open access.